New Designs for Nuclear Reactors

Innovations in nuclear design are tackling problems like the ones that contributed to the Fukushima Daiichi disaster in Japan. WSJ's Rebecca Smith reports.

This transcript has been automatically generated and may not be 100% accurate.

... I ... long before the disaster at Fukushima Daiichi ... nuclear engineers were working on solutions to problems like the ones that contributed to the accident in Japan ... some of these improvements are included in the designs of the latest generation of reactors ... so far American utilities are building only one kind of new reactor ... the key one thousand ... design by Toshiba's Westinghouse unit ... it's been chosen by two utilities ... southern Company and Scana Corporation ... for projects in Georgia and South Carolina ... it is also being used it to sites in China ... the AP one thousand uses something called passive safety systems ... and employee natural forces like gravity and conviction ... to keep reactor stable in an emergency ... this means less operator intervention is required ... for example ... large reservoirs of water are stored above the reactor ... and gravity pulls the water down to the reactor core is needed ... existing reactors rely more heavily on electrically driven pumps and valves ... to maintain proper fluid levels and temperature settings ... so if reactors lose pretty electricity ... they begin running out of coolant in a few days and can oversee an even meltdown ... and if other backup systems don't kick in ... the crisis can escalate ... that's what happened at Fukushima ... the new reactors can also be built in modular fashion ... using factory assembly line techniques ... this improves safety because it means reactors have fewer quirks ... an operator trained to work in the control room of one EP one thousand ... should be able to step into the control of another ... and know what's going on ... that safety experts still worried that even the new reactors will be able to withstand extreme advance like enormous earthquakes were seen on needs ... scientists say future generations of nuclear plants may be built underground ... and designed so that if there were serious problem ... they would wind down ... as one scientist told us operators would simply walk away ... for The Wall Street Journal this is Rebecca's man in San Francisco ...